<!DOCTYPE html>
<html lang="zh-CN">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>

<body>
    <script>
        const str = 'haha哈哈哈哈，斤斤计较'
        // 定义规则
        const reg = /哈哈/
        //看看是否匹配有
        console.log(reg.test(str));

    </script>
</body>

</html>